B - Operations – Transporting – 29 – C
Patent
B - Operations, Transporting
29
C
18/677
B29C 47/66 (2006.01) B29C 44/34 (2006.01) B29C 47/10 (2006.01) B29C 47/36 (2006.01) B29C 47/50 (2006.01)
Patent
CA 1189266
ABSTRACT OF THE DISCLOSURE Method and means are provided herein for entraining gas as a blowing agent in a thermoplastic melt to provide foamed thermoplastic extrudate. The method includes providing an extruded flowing mass of thermoplastic melt. The flow of the melt is constained into a tubular configuration over a finite distance. An annular sheet-like flow of gas is impinged under pressure on the tubular configuration of melt substantially transversely of the direction of flow thereof to entrain the gas in the melt. Subsequently the melt with entrained gas is returned to a flowing mass configuration, where the flow rate and temperature of the flowing mass with entrained gas is controlled to optimum values for subsequent extrusion. Finally, the flowing mass, with entrained gas is extruded to produce the foamed thermoplastic extrudate. The cell pressures achievable by the present invention are higher than the cell pressures achievable by fluorocarbon blow- ing agents and therefore, less brittleness is an intermediate benefit achieved by the present invention in the ultimate extruded foam products. The oriented foams have been stretch oriented 1.5 times initial dimensions in both the machine and transverse directions of extrusion and this has been found to be highly satisfactory in producing foams of reduced brittleness and enhanced structural strength.
414685
Borden Ladner Gervais Llp
Maryland Cup Corporation
LandOfFree
Method and apparatus for generating foamed thermoplastic... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for generating foamed thermoplastic..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for generating foamed thermoplastic... will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-1232719